What would happen if every human on planet Earth spontaneously disappeared? How long would it take for Mother Nature to reclaim the landscape and return to her primordial roots? That's the theory that distinguished journalist Alan Wiesman poses in his book The World Without Us. The results of this theory are fascinating. After a few short days without power, the Hudson River would start to reclaim the subway of New York City. The Panama Canal, perhaps one of man's greatest technological achievements, would spill over to flood the Isthmus of Panama after a mere 20 years without maintenance. Wiesman engages the reader with discussions of just how quickly the earth would reclaim man-made structures. However he also reports from areas where the natural environment exists with little to no human influences like Poland's ancient Bialowieza Forest or the stark Korean Demilitarized Zone. This books' subject matter is fantastically simple and yet exploring this topic is both interesting and shocking. This engrossing piece of nonfiction not only vividly describes the natural wonders of planet Earth but also the ephemeral nature of humankind.